Cigarette lighters, particularly of the disposable type, are known which comprise, within a hollow body, a reservoir of combustible liquified gas, a pressure reducer mounted on an outlet of the reservoir and a burner with a valve on top of the pressure reducer, and means for igniting the gas escaping from the burner after the valve is opened. This igniting means most often consists of a wheel bearing against a flint, rotation of the wheel producing sparks which are projected over the burner.
Another solution which is becoming more widespread consists in substituting a piezo-electric igniter for the flint-wheel assembly. In both cases, the gas of the cigarette lighter is ignited by pressing on a thumb-piece which is either pivoted on the body of the cigarette lighter or which slides within the body. In addition to creating one or more sparks, the thumb-piece lifts the burner as it moves, which releases the gas which is to be ignited.
The thumb-piece is pressed by the user of the cigarette lighter. However, such depression may occur accidentally, for example in a pocket, or by an unauthorized "user" who might misuse the cigarette lighter.
In order to overcome this drawback, the provision of locking means for the thumb-piece has been proposed. When the thumb-piece is locked, the gas cannot escape from the reservoir and no spark can be generated. This is the safe position.
However, in order to use the cigarette lighter, the thumb-piece has to be unlocked without requiring any special skill. To this end, a "before igniting" position must exist in which the cigarette lighter is ready to operate simply by pressing on the thumb-piece as in the usual operation.
A cigarette lighter is described in FR-A2 633 702 which is provided with locking means in which there is a locked position of the thumb-piece and a stable unlocked position allowing conventional operation of the cigarette lighter. From the locked position, the safety mechanism is unlocked during a first time period. After this unlocking, the user can ignite the cigarette lighter at any time. Pressing on the thumb-piece automatically returns the locking mechanism to the locked position.